Building system, beam element, column and method

ABSTRACT

The present invention provides a building system, including at least partially hollow building elements, in which hollow spaces of the building elements connect to one another for the passage of lines. The hollow spaces are accessible and remain accessible via openings in the building elements for fitting or removing the lines. The building elements include a beam element, a column, a wall element and/or a floor element. A reinforcement arranged inside the building elements comprises parallel rods, to which supporting elements are attached by at least one a double weld.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of European Application No. EP05077675.6, filed Nov. 28, 2005, the contents of which is incorporatedby reference herein.

FIELD OF THE INVENTION

The present invention relates to a building system, to a beam element, acolumn and to a method for constructing a building using a system ofthis type.

The building system may comprise all structural components forconstructing a building. The system, a building element and/or themethod is, for example, used in the construction of houses as well asoffices and commercial properties.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 4,261,150 discloses a system of wall elements. Theelements comprise two parallel concrete slabs which are arrangedparallel to one another with an intermediate space in between and areconnected to one another by a reinforcement. During building, the wallelements are provided with a support from the outside. Once the elementshave been arranged in the desired position and the lines have beeninstalled in the intermediate space, concrete is poured into theintermediate space between the two concrete slabs in order to providethe building elements with the desired strength in order to absorbtransverse forces. The lines comprise, for example, electrical wiring,telephone and computer wiring and/or supply and discharge pipes for gasand water.

DE-44 34 499-A1 discloses a building system comprising floor elementsand walls that are provided with hollow spaces. FIG. 26A shows a floorelement 300. During construction, the hollow spaces 302 of the walls arefilled up using concrete 304. The floor elements comprise two parallelslabs 306, 308 that are connected to one another by a reinforcement. Thereinforcement comprises straight bars 310, 312. The bars are connectedby bent bar 314. The lower slab 306 is a constructional, or supportingslab, whereon a layer of concrete 304 is poured for bracing thereof. Theupper slab 308 obstructs the view of heating pipes, which are arrangedin between the slabs. Supports for strengthening are arranged in betweenthe layer of concrete 304 and the upper slab 308; The upper slab isprovided with square openings, which are sealed during constructionusing poured concrete.

The building elements of the known system are relatively light andhollow before the concrete is poured in, resulting in advantages withregard to transport costs. However, the disadvantage of the system isthat, like with other buildings having solid walls and floors, fittingor modifying lines retrospectively is labour intensive. Fitting ormodifying lines requires walls to be broken open, slots to be cut, holesto be drilled, etc. with the associated nuisance and costs. In thepresent day and age, where communication means change quickly and thedemand for the supply of (electrical) energy is growing constantly, thislimited degree of flexibility is a major drawback.

The limited load-bearing capacity of a floor element 300 according toDE-44 34 499-A1 as shown in FIG. 26A limits the maximum thickness d1thereof to 40 cm. A height d2 of the hollow space of the floor elementsis 5 cm at most. A diameter of the bars 310, 312, 314 of thereinforcement is limited to 10 mm or less. Parts of the reinforcementwill warp when using larger diameter, as indicated by line 320. Thus thestrength of the reinforcement is limited.

System ceilings and system floors are also known. Lines, such as sewerlines, wires of a computer network or for air conditioning, are arrangedon top of and/or underneath a solid floor. The lines are then hiddenfrom view by means of a system floor or a removable system ceiling.However, fitting the system ceiling is labour intensive as the lines andthe system ceiling have to be fitted to the floor. Furthermore, theabove-mentioned drawbacks with regard to lines having to be led throughthe floor remain, as cutting, drilling and the like are necessary.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a system of buildingelements in which lines, and modifications thereto, can be fittedrelatively simply.

To this end, the invention provides a building system, comprisingbuilding elements provided with hollow spaces, in which the hollowspaces of the building elements connect to one another for the passageof lines.

As a result of the system according to the invention, lines can befitted and removed more easily. As the building elements are partiallyhollow, the lines remain accessible after the building works have beencompleted, so that making modifications retrospectively is lessdisruptive since breaking and cutting is deviated.

In one embodiment, the hollow spaces of the building elements areaccessible via openings in the building elements for fitting or removingthe lines. Modifications or additions in the hollow spaces can thus bemade via the openings even after construction work has finished, withoutthe need of breaking and cutting.

Preferably, the building elements comprise a beam element and/or acolumn. In addition, the building elements may comprise a wall elementand/or a floor element.

In one embodiment, the building elements comprise an internalreinforcement, which reinforcement comprises at least two rods arrangedapproximately parallel and connected to one another by a number ofsupporting elements. Such supporting elements are also known as strutrods. The supporting elements are attached to the rods by means of atleast one double weld. The double weld is a strength weld, i.e. a forceexerted on the respective supporting element is transferred to the rodvia the weld substantially entirely.

Preferably, the double weld comprises two weld spots which are arrangedat opposite sides of an end of the supporting elements.

If only one weld seam is used, a rod may bend or hinge about the weldseam and may even break away. By using two weld seams, preferablyopposite one another on a supporting element when viewed head on, thewelds cannot act as a pivot and, at the same time, a stronger connectionis achieved. Simultaneous welding of the two seams prevents thesupporting element from becoming warped during welding. Simultaneouswelding is preferably carried out using a welding robot, which not onlywelds simultaneously, but also for an equal period and over an equallength of every weld seam. In this manner, identical and strong weldedjoints are produced which generate as little tension as possible in therods.

According to another aspect, the invention provides a beam element for abuilding system as described above, comprising:

-   -   an elongate beam member;    -   a reinforcement provided in the beam member;    -   a hollow space extending inside the beam member for arranging        lines therein.

The beam element preferably comprises at least two rods arranged in thebeam member and extending in a longitudinal direction of the beammember, and supporting elements which are fitted to a rod by their firstend and to another rod by their second end. The entirety made up of rodsand supporting elements is also referred to as a zigzag girder.

In one embodiment, the ends of the supporting elements are attached tothe respective rod by means of at least a double weld.

In one embodiment, the beam member comprises a bottom part which iswider than a top part arranged parallel to the bottom part. The bottompart is at least partially wider than the top part in order to providean edge on which floor parts can be arranged.

Preferably, the bottom part is a first slab. The top part is preferablya second slab which is arranged parallel to the bottom part. The firstand second slabs are separated from one another by the reinforcement forassimilating transverse forces in the hollow space. The reinforcementcan assimilate transverse forces in the hollow space, because thereinforcement comprises straight supporting elements which are connectedto the rods by means of a double weld (power weld). As a result of thesolid construction of the reinforcement, the latter is able to absorbforces, thus making the creation of the hollow space between the bottomand top parts possible. The hollow space may even be shaped in such away that the concrete bottom and top parts are partially separated fromone another by just the supporting elements, which are partially free ofconcrete. The beam element according to the invention is for examplecapable of spanning a width of at least 20 m and at the same timesupporting a load of around 35 kg/m2.

According to another aspect, the invention provides a column for abuilding system according to one of the preceding claims, comprising asupport member provided with a hollow space, a reinforcement beingarranged inside the support member.

In one embodiment, an opening is provided in a side wall of the supportmember in order to make the hollow space accessible.

Preferably, the column comprises a collar or shoulder which is widenedrelative to the support member in order to arrange a building elementthereon.

According to another aspect, the invention provides a method, comprisingconstructing a building from building elements provided with hollowspaces, in which the hollow spaces of the building elements connect toone another for the passage of lines.

The load-bearing capacity of the reinforcing structure is such that thehollow space in the building elements does not have to be filled withany other material in order to achieve sufficient load-bearing capacity.Thus, any lines in the hollow spaces can be moved, replaced, repaired oradded. Likewise, it is possible to add additional connections to lineswhich have already been installed.

The above described building elements are rigid and have a largeload-bearing capacity. The metal used for the reinforcement ispreferably steel and in particular reinforcing steel. Furthermore, it ispreferable for the supporting elements and/or the rods to be tubular,thereby further increasing the strength of the reinforcement. Solidsupporting elements are feasible too.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages and characteristics of the present invention will beexplained in greater detail below with reference to the attacheddrawings, in which:

FIG. 1 shows a sectional view of a building element according to thepresent invention;

FIG. 2 shows a side view, partially in section, of a wall and a floorelement according to the present invention;

FIG. 3 shows a sectional view of a floor element according to thepresent invention;

FIG. 4 shows a sectional view of a wall and a floor element according tothe present invention;

FIG. 5 shows a sectional view of a floor and a wall element which areconnected to one another;

FIG. 6 shows a floor element according to the present invention, inwhich an intermediate space between concrete slabs of the floor elementis accessible from below;

FIG. 7 shows a top view of an embodiment of a system according to thepresent invention, comprising a column, beam elements and floor elementsarranged thereon;

FIG. 8 shows a perspective view of a first embodiment of a beam elementaccording to the invention;

FIG. 9 shows a section of the system of FIG. 7 along the line B-B;

FIG. 10 shows a section of the system of FIG. 7 along the line A-A;

FIG. 11 shows a top view of a column according to the present invention;

FIG. 12 shows a view of a sectional or modular system of a floorcomprising a number of floor elements according to the presentinvention, without additional poured concrete layer but connected using(metal) strips;

FIG. 13 shows a view of a floor comprising modular floor elements as afinal element according to the present invention;

FIG. 14 shows an embodiment of a floor element and a wall element of amodular system according to the present invention;

FIG. 15 shows a section of the system of FIG. 7 along the line B-B inanother modular embodiment;

FIG. 16 shows a section of the system of FIG. 7 along the line A-A inthe modular embodiment of FIG. 15;

FIG. 17 shows a perspective view of a rod and a supporting element witha double weld according to the present invention;

FIG. 18 shows a diagrammatic view of the double weld of FIG. 17;

FIG. 19 shows a diagrammatic representation of a first step for theproduction of a building element according to the present invention;

FIG. 20 shows a diagrammatic representation of a second step for theproduction of a building element according to the present invention;

FIG. 21 shows a diagrammatic representation of a first step for theproduction of a beam element according to the present invention;

FIG. 22 shows a diagrammatic representation of a second step for theproduction of a beam element according to the present invention;

FIG. 23 shows a view of an embodiment of a concrete column according tothe present invention;

FIG. 24 shows a longitudinal section of a column according to thepresent invention during a first production step; FIG. 25 shows alongitudinal section of a column according to the present inventionafter a further production step;

FIG. 26A shows a prior art floor element provided with reinforcement;

FIG. 26B shows a sectional side view of the reinforcement of FIG. 26A;

FIGS. 27-30 show sectional side views of embodiments of thereinforcement according to the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a building element 2 which comprises a first concrete slab4 and a second concrete slab 6. Along a part of the length of theconcrete slab, the second concrete slab 6 has a smaller width than thefirst concrete slab 4, the width being in the plane of the paper. Thelength of the first concrete slab 4 may be equal to the length of thesecond concrete slab 6 or one of the two lengths may be less than thelength of the other slab, depending on the application and the chosendesign. A metal load-bearing structure is arranged between the first andthe second concrete slab 4, 6. The building element comprises a firstsupporting element 8 a and a second supporting element 8 b. Thesupporting elements 8 a and 8 b are at an angle with respect to oneanother for the purpose of structural rigidity and strength.

If desired, a building element 2 may comprise more supporting elements,for example depending on the desired width of the building element 2, aminimum weight to be supported or a span to be bridged.

FIG. 2 shows a floor element 8 with two slabs 4, 6. Rods 10 a, 10 b arearranged inside the slabs in the longitudinal direction. The rods 10 a,10 b are connected to one another by supporting elements 12 a, 12 b, 12c, etc. Adjacent supporting elements 12, such as 12 a and 12 b, togetherwith one of the rods 10 a, 10 b, form a triangle. The triangle'sgeometry is determined on the basis of a height of the building elementand a desired strength.

One end of the floor element in FIG. 2 rests on a wall 14. The floorelement is supported at at least one other position. Preferably, thefloor element is supported at a position where one or two supportingelements 12 are connected to the rod 10 b. Thus, the transverse force istransferred to a support of the floor element, such as the wall or thewall element to which the floor element is affixed.

The configuration, shown in FIG. 2, of the rods 10 a, 10 b and thesupporting elements 12 in the shape of adjacent triangles was chosen forreasons of structural strength and rigidity which are associated with atriangular configuration of this type. Other configurations are alsopossible, as long as the strength of the structure remains sufficient.

The supporting elements 12 are welded to the rods 10. For addedstructural strength, one end of each supporting element 12 is welded inat least two spots, or along two seams, to a rod 10 a, 10 b. Optionally,more than two welding spots may be used. The one weld may, for example,be executed on a first side of the respective end, while the second weldis executed on a second side situated opposite the first side.

When a supporting element is welded in one spot or along one seam, as inthe prior art and as shown in FIG. 26B, an eccentric load arises at therods 310, 312. De bars may deform, as indicated by line 320. Thisrenders welding along a second seam or to the opposite rod difficult orimpossible. Furthermore, undesirable stresses may occur in the buildingelement. Furthermore, using thicker elements is impossible, so thestrength of the reinforcement is limited.

Preferably, the supporting elements are welded simultaneously to a rod10 a, 10 b at the two spots or along the two seams. In this case it isadvantageous if this welding is carried out by an automatic weldingdevice since such a device produces two (or more) substantiallyidentical welds, as a result of which stresses in the respectivematerials are further reduced. Deformation of the supporting elements 12is prevented further by simultaneously producing a total of four weldsat two ends of the supporting elements 12. Thus, it is possible toproduce flat building elements of sufficient strength.

FIG. 3 shows a third embodiment of a floor element comprising aplurality of building elements 2. The floor element of FIG. 3 comprisesconcrete slabs 6 which are connected by means of a load-bearingstructure to concrete slabs 4 which are arranged in parallel. Theload-bearing structure comprises two or more supporting elements 20 a,20 b, 20 c. The use of a plurality of supporting elements results in agreater load-bearing capacity and/or greater rigidity. Thus, widerand/or longer concrete slabs 4, 6 can be used. Also, a load-bearingstructure of this type can be used in order to enable a floor element tobear larger loads.

The floor element from FIG. 3 comprises adjacent building elements 2.The concrete slabs 4 form a continuous surface. This continuous surfacemay, as illustrated, be located at the bottom and act as a ceiling, butmay also be located on any other side, depending on the use.

Openings between the concrete slabs 6 are covered with a covering panel26. The covering panel 26 can be made from any material, depending onthe desired strength and use. The covering panels 26 and the concreteslabs 6 together form a surface, the covering panels, if desired, beingand remaining removable in order to access the space between theconcrete layer 22 and the concrete slabs 6.

A concrete layer 22 is arranged in the space between the two concreteslabs 4, 6, on the concrete slabs 4. The concrete layer 22 comprises areinforcement 24 above a joint between adjoining building elements 2.The concrete layer 22 ensures a diaphragm action in the building whereit is fitted, as a result of which the floor element is reinforced.Diaphragm action ensures that the floor acts as a unit in transferringforces onto the walls of the building, without the components of thefloor moving with respect to each other. Floor parts can also be securedto one another using bolts, as is described in more detail below.Incidentally, depending on the use, the space between the concrete slabs4, 6 may be partially or completely filled with concrete, cellularconcrete or another material, for example a sound or vibration-dampeningmaterial and/or a thermal insulation material.

There is a space between the concrete layer 22 on one side and theconcrete slabs 6 and the covering panels 26 on the other side forinstalling electrical cables 29 and other lines 30. The covering panels26 have been fitted so as to be removable and replaceable, so that thelines 29, 30 are easily accessible. In case of malfunctions, new linesand/or pipes can easily be installed in the gap by removing a coveringpanel 26. In FIG. 3, the electrical cables 29 are connected to anelectrical junction box 28, which is arranged in a concrete slab 4.

Depending on the construction of the load-bearing structure, thematerials used and the form of the supporting elements 12, 20 and thegirders 10, 24, etc., the building elements 2 can bridge spans of forexample approximately 20 meters.

FIG. 4 shows a floor element comprising a building element 2. The floorelement is connected to a wall element 42 according to the presentinvention. The building element 2 comprises a first concrete slab 4 anda second concrete slab 6, the first concrete slab 4 being wider than thesecond concrete slab 6. As a result of the first concrete slab 4 beingwider than the second concrete slab 6, the floor element is arranged onthe supporting wall structure of slab 44 by means of the protruding partof slab 4.

In the embodiment shown in FIG. 4, the first concrete slab 4 rests on afirst concrete slab 44 of the wall element 42. The second concrete slab46 may be higher than the first concrete slab 44, namely such that theend side of the second concrete slab 46 is level with the top of thefirst concrete slab 4 of the floor element 2.

It can be seen from FIG. 4 that an intermediate space between the firstslab 4 and the second slab 6 is greater than a space between slab 44 andslab 46. Such a difference in dimensions is not required but onlydepends on the desired strength. All dimensions of the building elementsmay be selected to be different, depending on function and desiredstrength and space and other parameters.

In addition to the rods 10, supporting elements 12, concrete layer-22and lines 30 already shown in the previous figures, FIG. 4 shows areinforcement 24 which provides a connection between the concrete layer22 and the first concrete slab 44 of the wall element 42. Thereinforcement 24 provides an anchoring between the floor element 2 andthe wall element 42. The lines 30 in the floor element are connected tothe lines 30 in the wall element 42 by means of a coupling piece 31. Acoupling piece 31 is optional, but facilitates installation of the lines30.

The space between the concrete slabs 44, 46 of the wall element 42 mayremain empty, except for the lines 30 installed therein. Likewise, thisspace can at least partially be filled with material, for example soundinsulation, thermal insulation material, sand or concrete, depending onthe desired properties of the wall.

FIG. 5 shows another embodiment of a connection between a wall and afloor element according to the present invention. A first concrete slab4 rests on a wall element 42A, while a second, relatively small concreteslab 6 above it forms part of a floor. A filling material 22, forexample concrete, is disposed in a first wall element 42A.

A second wall element 42B is arranged on the first wall element 42A. Thesecond wall element 42B comprises two concrete slabs 44, 46, which areof equal height. The second wall element 42B is likewise filled with amaterial 48. Preferably, the filling material 48 is the same as thefilling material 22 with which the first wall element 42A is filled andthe material 48 provides a connection to the filling material 22.Although this has not been shown, a reinforcement material may bearranged in the filling material 22, 48 in order to further reinforcethe connection. The filling by means of filling material is optional.

FIG. 6 shows a further embodiment of a building element according to thepresent invention. The building element acts as a floor element. Thefloor element comprises a first concrete slab 4 which forms a continuousfloor surface with the adjacent building elements. The building elementfurthermore comprises two concrete slabs 6 a and 6 b which are eachconnected separately by means of a load-bearing structure comprisingsupporting elements 20 to the first concrete slab 4. The concrete slabs6 a and 6 b form a ceiling for a storey running beneath the buildingelements. Covering panels 26 close the openings between slabs 6 a and 6b. The covering panels 26 are removable so that lines 30 are easilyaccessible. Connections for the lines 30 are provided in the coveringpanels 26, as well as for example an electrical junction box 28.

In order to provide a structure with diaphragm action, see above, acover layer 32 may be provided on the slabs 4 of the floor element. Inaddition, a reinforcement may be arranged in the cover layer 32.

Above, building elements are described for forming at least partiallyhollow floor and/or wall elements. In the intermediate space between thebuilding elements, lines can be arranged. The intermediate spaces areaccessible via openings, so that modifications can be made to the linesretrospectively. In this case, crushing, cutting or similarly radicalactions can be dispensed with.

In addition to floors and walls, a building constructed using theabovementioned building elements generally also comprises beam elementsand columns. The supporting columns are arranged at angular points ofthe floor elements and are placed in an upright position, at rightangles to the floor element. The beam elements extend from column tocolumn. Floor elements are arranged on protruding edges of the beamelements. The beam elements also provide additional strength, as aresult of which taller or narrower buildings can be constructed.

Known supporting beams and columns are made of solid concrete. Anyreinforcement arranged therein is fitted under tension, as describedabove, as a result of which the reinforcement is too weak to absorbtransverse forces on its own. By applying concrete around thereinforcement, the transverse forces are absorbed by the solid concrete,i.e. the concrete around the supporting elements prevents buckling ofthe supporting elements. With known columns and beam elements, the linesare therefore embedded in concrete. Thus, chases have to be cut ifmodifications are to be made.

The present invention provides a beam element and a column which areprovided with a hollow space in which lines can be arranged. The hollowspaces of the beam elements and the columns preferably connect to theintermediate space of the wall and floor elements via openings in sidewalls of the columns, so that the unit provides a complete system forthe passage of lines. Even after the building has been completed, thehollow spaces are accessible so that modifications can be made.

FIG. 7 shows a system which includes hollow columns and beam elements inaddition to floor and wall elements. The system comprises floor parts 50which consist of floor elements 2 as described above. The floor partspartially rest on a beam element 54 by their outermost edges 52. Thebeam element 54 and a second beam element 56 rest on a column 58 by oneof their ends. The beam element 56, like the beam element 54, comprisesa top part 60 which is at least partially narrower than a wider bottompart 62. The floor parts 50 are supported by the edge of the bottom partwhich protrudes relative to the top part 60. The protruding edge isindicated on the right-hand side of FIG. 7 by means of a dashed line.

FIG. 8 shows an embodiment of a beam element 54 according to the presentinvention. The beam element comprises a top part 60 and a bottom part62. The bottom part comprises a first slab and the top part comprises asecond slab. The first and the second slabs are preferably made ofconcrete. The first and second slabs are furthermore parallel to oneanother and are connected to one another by means of a reinforcement.The reinforcement comprises rods which are embedded in the concrete ofthe slabs, and are therefore not visible in the figure, as well assupporting elements 92, 94. The supporting elements 92, 94 are arrangedin pairs in the longitudinal direction of the beam element. As thesupporting elements are optionally arranged at an angle to one another,transverse forces, in the plane of the top part 60, are more readilyabsorbed.

The supporting elements 92, 94 are welded to rods 96, 98 by means of theabovedescribed welding method (FIG. 9). The locations of the welds aredenoted by spots 100, 102, 104. By applying the abovedescribed weldingmethod, the reinforcement is able to absorb transverse forces morereadily. In addition, the fact that the supporting elements arepartially embedded in the concrete has proved to be advantageous. Thesupporting elements are further strengthened by partially embedding themin a poured layer of concrete 22, which is also provided in the hollowspace of the floor parts 50. The buckling length of the supportingelements is thus only approximately half the length of the section ofthe supporting elements which is free from concrete.

FIG. 9 shows a column 58 of the system according to the invention. Thecolumn comprises an upright longitudinal support member 132. One end ofthe support member is provided with a widening shoulder part or support134 on which the beam elements 54, 56 are arranged (see also FIG. 7).The beam elements 54, 56 comprise a top and a bottom part which areseparated by a hollow space, as described with reference to FIG. 8.Floor elements 50 according to FIGS. 1 to 6 are arranged on the edges ofthe component 62 of the beam elements. The hollow space of the beamelement 54, 56 is in communication with the hollow space of the floorelements so that lines can be lead through.

A second column 140 arranged on the shoulder part forms an upper storey.The second column 140 is anchored in the lower column 58 by means of aninternal reinforcement 142, 144.

The columns 58 and 140 are partially hollow. In the embodiment shown,the columns are provided with en elongate hollow space 146 over theirentire length. At a location which adjoins the hollow spaces in the beamelements 54, 56 or in floor elements 50, the second column 140 isprovided with an opening 148. The opening 148 extends from the hollowspace 146 through the side wall of the column to the outer side of thecolumn. Optionally, several openings 148 are provided in the side wallof the column in suitable locations.

The cross section shown in FIG. 10, which is at right angles to thecross section shown in FIG. 9, shows floor parts 50 arranged on thebottom section 62 of the beam element 54. In the embodiment of FIG. 10,the reinforcement of the beam element 54 also comprises rods 166, 168arranged in the width direction of the beam element. The rods 166, 168connect the rods 96 and 98, respectively. The supporting elements 92, 94are arranged in parallel planes which are at right angles to thedrawing. The supporting elements may however be arranged aslant. Thesupporting elements are connected to the rods 96, 98 according to thewelding method described above.

FIG. 11 shows the column 58, which is, for example, approximately squarein top view. The hollow space 146 arranged in the centre of the column58 is also approximately square. Reinforcement rods 142, 144 arelikewise shown.

In another embodiment of the system, illustrated in the figures up to16, the building elements are connected to one another by means ofbolts. Furthermore, similar parts are denoted by the same referencenumerals.

FIG. 12 shows a floor comprising floor elements 2. The floor elementcomprises a slab 4 and a narrower slab 6. The intermediate space betweenslabs 6 is filled by a lid 26. The reinforcement of the floor elementscomprises rods 10 which are connected by supporting elements 12. Thefloor elements 2 are connected to one another by a removable coupling202, instead of with a poured concrete layer 22 as in FIG. 3. Thecoupling comprises a part 200 anchored in the slabs 4. The parts 200 ofthe respective slabs 4 are connected to one another by means of asuitable connecting piece.

The detachable coupling of the building elements which is describedbelow in more detail has the advantage that the building elements can bereused, i.e. if a building has to be demolished, the couplings can bedetached and the building parts can be removed intact. The buildingelements can then be used in the construction of a new building, thuspreventing debris and reducing the demand for material.

The detachable coupling is preferably formed by nuts and bolts. Thebolts 204, if desired provided with anchors 206, are embedded in theconcrete of slabs 4 (FIG. 13). The bolts are coupled by a plate 208 andnuts 210 are provided on the ends of the bolts.

In a similar manner, floor parts can be connected to a wall, as shown inFIG. 14. A bolt 216, provided with a cramp iron, is embedded in a panel212 of a wall 214. A hole is provided on an edge of slab 4 of the floorelement, through which the bolt protruding from the panel 212 extends.At the bottom of another panel 218 of the wall, a hole 220 is provided.Via the hole 220, a nut 222 is fitted in order to fixedly attach theparts of the entire unit to one another.

As shown in FIG. 15, the column 58, for example, comprises bolts 230,232, embedded in a similar manner and protruding from the top end of thecolumn. The ends of the beams 54, 56 comprise holes 234, 236, into whichholes nuts 238, 240 can be fitted on the bolts in order to bolt the beamelements to the column. At one top end of the column 58, a metal strip242 is provided over part of the periphery, which strip liesapproximately at the top of the column. A corresponding metal strip 244is provided at the bottom end of the column 140. The columns 58 and 140are connected to one another by welding edges of the strips 242, 244together. The strip 242 is anchored in the column 58 by embedded crampirons 246, 248.

FIG. 16 shows another view of the system of FIG. 15 and, in additionshows that floor elements 50 are bolted to the embedded bolts 254, 256by means of nuts 250, 252.

FIG. 17 shows the double weld according to the invention. Supportingelement 258 is attached to rod 260 by applying a weld 264, 266 at theend 262 of the supporting element on two opposite sides.

FIG. 18 shows that the joint surface of the welds 264, 266 is greaterthan or equal in size to the surface of the supporting element 258.Thus, a strong coupling is achieved, in which the forces exerted on thesupporting element are completely passed on to the rod 260.

FIG. 19 shows a first manufacturing stage of a floor or wall element 2.First, the slab 6, provided with reinforcement 10, 12 is cast in a firstshuttering 280. As shown in FIG. 20, the entire unit is turned over oncethe concrete has set. Then, slab 4 is cast in shuttering 282.

A first manufacturing stage for producing a beam element according tothe invention, as shown in FIG. 21, comprises casting the top part 60 ina shuttering 290. The reinforcement 294, comprising rods 166, 168 andsupporting elements 92, 94 is also embedded. After setting, the entireunit is turned over in a second manufacturing stage, as shown in FIG.22. Then, the component 62 is cast in a second shuttering 292.

The beam element may, for example, be produced as shown in FIGS. 21 and22. The concrete top part 90 is cast in a shuttering containing thereinforcement and any pipes or blocks for creating openings (FIG. 21).The entire unit of set top part 90 and reinforcement is turned 180degrees about a longitudinal axis and placed on the open side of theshuttering of the bottom part 88. Then, the bottom part 90 is cast (FIG.22). This manufacturing method has the advantage that the top and bottomof the beam element are clean when the shuttering has been removed. Afinishing coat is thus obviated.

The column may comprise an opening 190 in a side wall of the supportmember 132, as shown in FIG. 23, similar to the opening 148 in FIG. 9.Lines arranged in the hollow space of the column 146 are accessiblethrough the opening 190. In the opening 190, connections are providedfor example, such as sockets. The opening 190 may optionally be providedwith a door in order to render the lines arranged inside the columninvisible, if the opening 190 is arranged in a visible spot, for exampleat hip or eye level from the floor.

The hollow column can be produced by pouring concrete in two parts intoa shuttering, see FIGS. 24 and 25. The hollow space 146 inside thecolumn can be produced by, for example, arranging an elongated sheath,tube or a block made of polystyrene foam in the shuttering beforepouring the concrete. In addition, the desired reinforcement 191 isarranged in the shuttering before the pouring. As shown in FIG. 24, afirst part having three walls 192, 194, 196 is poured first. Once saidwalls have set sufficiently, the entire unit is turned 180 degrees aboutthe longitudinal axis in a second stage, following which a last wall 198is cast in a shuttering (FIG. 25).

It is likewise possible to cast the column in a shuttering in a verticalposition, the hollow space being produced by a tube arranged in theshuttering.

The present invention provides a complete system for the construction.The beam elements act as beam binders where two floor parts meet and apassage for lines is nevertheless required. The beam element comprisesone or more hollow spaces for the passage of lines at virtually the samelevel as openings or hollow spaces in the floor parts.

After finalizing the construction, the hollow spaces remain accessible.The hollow spaces of the floor elements extend both in width and lengththereof. The covering panels 26 of the floor elements extend oversubstantially the entire length of the floor elements. Thus, thecovering panels 26 cover slitlike openings that provide access to thehollow spaces of the floor elements along substantially the entirelength of the floor elements.

As concrete beams are normally solid, the transverse forces occurringwhen the floor parts are being installed are absorbed by the concrete.With the beam element according to the present invention, it appearsthat the transverse forces can be absorbed by the zigzag arrangement ofthe supporting elements. The concrete which would normally absorb thetransverse forces can be omitted with the beam element according to theinvention in order to provide openings, since the reinforcement, interalia as a result of the welding method used, is sufficiently strong toabsorb the transverse forces. The openings or spaces may be connected tospaces in floors and walls.

The beam elements are coupled to the floor elements. The coupling can,for example, be achieved by the following two methods: 1) The beamelements are coupled to the floor elements by a cramp iron which isprovided at the first end in the beam element and at the second end inthe poured concrete layer 22; 2) the beam elements are coupled to thefloor elements by a mechanical coupling made of steel.

If the supporting elements of the zigzag-shaped girder arranged in thebuilding elements have relatively large diameters, for example adiameter between 20 and 40 mm, the supporting elements 170 can bearranged at right angles to the rods 166, 168, see for example FIG. 11.An inclined coupling of the supporting elements relative to the rods,see FIG. 8, is more stable in the top part 90 of the beam element. Thetop part 90 of the beam element forms the pressure zone and is subjectedto a buckling load.

The top of the beam element may be arranged so as to be level with thetop of adjoining floor elements. Optionally, a finishing layer 32 (seeFIG. 6) may be added on top. The finishing layer may for example serveto compensate for relatively large tolerances.

FIGS. 27-30 show embodiments of a reinforcement according to the presentinvention. The reinforcement comprises rods that are connected using adouble weld. The reinforcement is applicable in all parts of thebuilding system according to the present invention.

FIG. 27 shows an embodiment having a rod 350 whereto a bar 352 isconnected using two welds 354, 356. The forces of the bar 352 aretransmitted to the rod 350 towards the centre line thereof. Preventingeccentric forces prevents deformation. As a result, thicker rods may beapplied as applied in known systems. Therefore, the reinforcement isstronger. Preferably, the rods 350, 352 are straight, to preventdeformation during welding.

FIG. 28 shows two parallel rods 350 whereto rods 352 are connected. Therods 352 meet at an angle α. The ends of the rods 352 are connected tothe rods 350 by welds 360-366. Both rods 350 are mutually connected byweld 368.

FIG. 29 shows two parallel rods 350 whereto rods 352 are connected. Therods 352 are parallel to each other. The ends of the rods 352 areconnected to the rods 350 by welds 370, 372, and 374. Both rods 350 aremutually connected by weld 376.

FIG. 30 shows three parallel rods 350 whereto two parallel rods 352 areconnected. The rods 352 are mutually parallel. The ends of the rods 352are connected to the rods 350 by welds 380, 382, and 384. Also, welds386, 388 mutually connect the three rods 350.

Application of the weld connections shown in FIGS. 27-30 enables hollowbuilding elements according to the invention to have larger hollowspaces than prior art elements.

The rods 350 and/or 352 may have a diameter larger than 10 mm. Rodshaving a diameter in the range above 16 mm are feasible. The rods remainstraight after welding.

Floor elements and/or beam elements may have an intermediate spacehaving a height d4 (FIG. 14) respectively d6 (FIG. 8) in the range of 15cm to 1 m. An intermediate space larger than about 1 m, for instance 1.5m, is feasible as well. The reinforcement according to the presentinvention enables to adapt the strength thereof to the desired dimensionof the intermediate space, for instance by applying multiple parallelrods, as shown in FIG. 29 or 30.

The welds may for instance be applied manually. The applied weldingmethod is for instance MIG welding, using CO2. In one practicalembodiment of the building elements, the supporting elements of thereinforcement have a diameter of 16 mm or more. Both ends of thesupporting elements are attached to the rods by means of double welds inorder to avoid deforming the supporting elements.

In one practical embodiment, the beam element can, for example, spanwidths of 5 m to 20 m. The beam element shown in FIG. 8 or 9, forexample, has a total height of approximately 60 cm to 80 cm. Thesupporting elements 92, 94 of the reinforcement have a diameter of 20 mmor more, for example of approximately 28 mm. Both ends of the supportingelements are attached to the rods 96, 98 by means of double welds toavoid prestressing the supporting elements.

The supporting elements and the rods of the reinforcement are made ofhigh-performance steel, such as torsteel, reinforcing steel orconstructional steel.

The supporting elements and/or the rods of the reinforcement have adiameter of for instance about 16, 20, 25, 28, 32 or 40 mm.

One practical embodiment of a column according to the invention may, forexample, have a length or height of 7 to 20 m, which is sufficient fortwo or more storeys of a building. The column, for example, in plan viewforms a square with sides of approximately 800 mm. The opening in thecentre is for example a square with sides of 400 mm. The column may besubjected to a maximum load of approximately 280 tons. The bottom part88 of the beam element laterally protrudes, for example, about 200 mmrelative to the top part 90.

The building elements according to the present invention are suitablefor use in buildings where the configuration of lines changes relativelyoften. Examples include hospitals, where electrical equipment is oftenmoved around and furthermore conduits for air treatment, oxygen and thelike have to be accessible near each bed. The present invention providesadvantages for offices with regard to modifying and adding electricalequipment which is required at each workstation. More and more airtreatment is being applied in this connection. Due to hollow spaces inthe building elements which are connected to one another and which areaccessible even after construction work has finished, it remainspossible to modify the lines relatively quickly and with relativelylittle disruption. A system comprising building elements according tothe present invention, for example, makes cable ducts on the wallsredundant.

The present invention is not restricted to the above embodiments anddimensions, to which many modifications can be made without departingfrom the scope of the attached claims.

1. Building system, comprising building elements provided with hollow spaces, in which the hollow spaces of the building elements connect to one another for the passage of lines.
 2. Building system according to claim 1, in which the hollow spaces of the building elements are accessible and remain accessible via openings in the building elements for fitting or removing the lines.
 3. Building system according to claim 1, in which the building elements comprise a beam element and/or a column.
 4. Building system according to claim 1, in which the building elements comprise a wall element and/or a floor element.
 5. Building system according claim 1, in which the building elements comprise an internal reinforcement, which reinforcement comprises at least two rods arranged approximately parallel and connected to one another by a number of supporting elements, the supporting elements being attached to the rods by means of at least a double weld.
 6. Building system according to claim 5, in which the double weld comprises two weld spots which are arranged at opposite sides of an end of the supporting elements.
 7. Building system according to claim 3, the beam element comprising: an elongate beam member; a reinforcement provided in the beam member; and a hollow space extending inside the beam-member for arranging lines therein.
 8. Building system according to claim 7, in which the reinforcement comprises: at least two rods; and supporting elements which are fitted to a rod by their first end and to another rod by their second end.
 9. Building system according to claim 8, in which the ends of the supporting elements are attached to the respective rod by means of at least one double weld.
 10. Building system according to claim 7, in which the beam element comprises a bottom part which is wider than a top part arranged parallel on the bottom part.
 11. Building system according to claim 10, in which the bottom part is a first slab, and in which the top part is a second slab which is arranged parallel to the bottom part and is separated from the first slab by the reinforcement and the hollow space.
 12. Building system according to claim 3, wherein the column comprises a support member provided with a hollow space, a reinforcement being arranged inside the support member.
 13. Building system according to claim 12, in which an opening is provided in a side wall of the support member, which opening extends from the hollow space to the outer side of the column in order to make the hollow space accessible.
 14. Building system according to claim 12, comprising a shoulder which is widened relative to the support member in order to arrange a building element thereon.
 15. Building system according to claim 1, wherein the hollow spaces provide an intermediate space greater than 15 cm.
 16. Building system according to claim 15, wherein the intermediate space is greater than about 1 m.
 17. Building system according to claim 15, wherein slabs of the building elements are relatively thin compared to the intermediate space.
 18. Building system according to claim 1, wherein the hollow spaces extend in both a length and a width direction of the building elements.
 19. Building system according to claim 2, wherein the openings extend over substantially the entire length of the building elements.
 20. Building system according to claim 5, wherein a diameter of the supporting elements of the reinforcement is greater than about 16 mm.
 21. Method comprising constructing a building from building elements provided with hollow spaces, in which the hollow spaces of the building elements connect to one another for the passage of lines.
 22. Method according to claim 21, comprising building elements provided with hollow spaces, in which the hollow spaces of the building elements connect to one another for the passage of lines. 